Made available in DSpace on 2015-12-03T18:32:55Z (GMT). No. of bitstreams: 1 Sandra_Regina_Chalela_Ayub.pdf: 418503 bytes, checksum: 43e6c0cb120d3ffc38d6d02e0cb0a11b (MD5) Previous issue date: 2002-04-24 / The fast and constant changes, in the business scenery, have evidenced the importance for the organizations to form and develop their human talents, in search of their competitiveness. Several companies recognize that training is important, in fact, basic for the organizations of the future, but they can find a problem - the resources used for the assimilation of the learning. In the sense of looking for answers for those new demands, the present research, work has as objective, to analyze and evaluate a learning resource - the use of the analogy in the learning process in business trainings. For its development, the interview methodology Focus Group was adopted. This way, it was possible to analyze and evaluate that the analogy facilitates the organizational; learning, therefore it can be used, in an effective way, as learning resource in training and business development; for it helps developing the abilities and knowledge requested in the learning organizations and that the five disciplines proposed by Peter Senge, for the learning organizations, can be developed through the analogy. / As r??pidas e constantes mudan??as, no cen??rio empresarial, t??m evidenciado a import??ncia de as organiza????es formarem e desenvolverem seus talentos humanos, em busca de seu diferencial competitivo. V??rias organiza????es reconhecem que o treinamento ?? importante, ali??s, b??sico para as organiza????es do futuro, mas poder??o encontrar um problema - os recursos utilizados para a assimila????o do aprendizado. No sentido de buscar respostas para essas novas demandas, o presente trabalho de pesquisa tem como objetivo, analisar e avaliar um recurso de aprendizagem - o uso da analogia no processo de aprendizagem, em treinamentos empresariais. Para o seu desenvolvimento, foi adotada a metodologia de entrevista Focus Group. Assim, foi poss??vel analisar e avaliar que a analogia facilita a aprendizagem organizacional; pode, portanto, ser utilizada, de forma eficaz, como recurso de aprendizagem em treinamento e desenvolvimento empresarial; pois, ajuda desenvolver as habilidades e conhecimentos requeridos nas organiza????es de aprendizagem e que podemos desenvolver as cinco disciplinas propostas por Peter Senge.

Uma nova ferramenta de aeroacústica computacional baseada em simulações RANS (Reynolds Averaged Navier-Stokes) foi desenvolvida para a predição do ruído gerado pelo escoamento tri-dimensional de jatos complexos. O método é denominado de LRT o qual surgiu da combinação da analogia acústica de Lighthill com o método de acústica geométrica Ray-Tracing. A grande vantagem da utilização do método LRT para predições de ruído é que este determina não apenas as fontes sonoras presentes no escoamento, mas também modela os efeitos da interação fluidoacústica e, sua influência no ruído em um campo distante. Esta característica tornou-se extremamente importante para a indústria de motores aeronáuticos já que investigações em bocais assimétricos estão atualmente em andamento devido à necessidade de redução de ruído. O método LRT é uma ferramenta relativamente rápida de predição de ruído de jatos baseado na Analogia Acústica de Lighthill e que usa como dados de entrada os resultados obtidos à partir de uma simulação RANS do escoamento. A interação fluidoacústica é calculada através da utilização da Teoria de Traçamento de Raios. O método LRT foi formulado como um método tri-dimensional e, portanto, não possui limitações de aplicabilidade para a predição sonora em relação ao tipo de escoamento ou à geometria do bocal. Diversas simulações numéricas foram conduzidas com sucesso para uma grande variedade de escoamento de jatos (jatos simples, coaxiais e assimétricos) utilizando o LRT como uma ferramenta de engenharia. O resultado deste trabalho é uma ferramenta numérica que permite a realização de predições de ruído para casos de escoamento de jatos complexos, assim como possibilita sua aplicação para a investigação de efeitos de interação do escoamento do jato com superfícies hiper-sustentadoras no campo acústico. Adicionalmente, o método LRT pode ser aplicado para complementar análises experimentais possibilitando, portanto, um melhor entendimento sobre os mecanismos fluidodinâmicos e acústicos presentes em escoamentos de jatos complexos. / A novel computational aeroacoustics tool based on RANS (Reynolds Averaged Navier-Stokes method) is developed for predicting the noise generated by complex three-dimensional jet flows. The new method is called LRT which arises from the combination of Lighthills acoustic analogy with Ray-Tracing acoustics. The powerful advantage of applying the LRT method for noise predictions is that it calculates not only the noise sources but it also models and takes into account sound-flow interaction effects without any geometric simplification, such as flow symmetries of the problem. This is now a strong requirement from aero-engines manufactures since investigations on asymmetric nozzles, as a means of noise reductions are in progress. The LRT method is a relatively fast jet noise prediction tool based on Lighthills Acoustic Analogy and it uses a Reynolds-Average Navier-Stokes (RANS) computational fluid dynamics (CFD) simulation as input information. The sound-flow interaction is computed by solving the propagation using Ray-Tracing equations. The LRT method has been formulated as a general three-dimensional method and it has no restrictions on the type of the flow field or nozzle geometry for noise prediction. Successful numerical noise predictions have been carried out for a variety of jet flows (single, coaxial and asymmetric jets) using the LRT as an engineering tool. The outcome from this thesis is a numerical tool that allows noise predictions of complex exhaust systems and the variations in sound field due to modifications of the flow field generated by the interaction of the jet flow with high-lift surfaces. In addition, the LRT method can be applied to complement experimental analysis providing a better understanding about the flow and acoustics mechanisms for complex jets.

La présente thèse se propose de réfléchir sur le caractère cinétique de la méthode analogique adopté dans le De motu animalium d’Aristote. En considèrant que l'objet du traité est la cause commune du mouvement et qu'Aristote en adopte une solution du type paradigmatique, d'une manière générale l'automotricité est le thème pendant que le membre articulé est le phore dans le raisonnement analogique du DMA. Nous considérons hypothétiquement que les stratégies plastiques sont le fil conducteur du raisonnement suivi par la recherche de la cause commune de la motricité pour tout mouvement. Notre double objectif général est, d’une part de tirer les acquis philosophiques sur le caractère immanent du principe du mouvement de la recherche menée dans le DMA et, d’autre part de percevoir le caractère cinétique et plastique de sa démarche, qui comporte des procédés méthodologiques dynamiques dans le but de s’adapter à l’objet. Ce que nous faisons en deux pas : premièrement par l’analyse des étapes de l’établissement du paradigme du membre articulé ; et en suite par l’analyse de l’analogie entre le membre articulé et l’automotricité animée. Les deux analyses visent saisir des éléments pour confronter les deux termes de l'analogie et vérifier la validité de toute la thèse et de la considération selon laquelle, la méthode analogique est un l'instrument plastique de la pensée de l'immanence. / This thesis proposes to reflect on the kinetic character of the analogical method adopted in De Motu Animalium of Aristotle. Considering that the object of the treatise is the common cause of the movement of animais, in general, automotricity is the "thème" while the articulated member is the ''phore" in De Motu's analogical reasoning. Hypothetically we consider that the plastic strategies of the analogical method of De motu are the guiding thread of the reasoning undertaken in the research on the common cause of the motility of ail animal movements. Our general double aim is: on the one hand, to take philosophical acquisitions on the immanent character of the principle of movement, and on the other hand, to grasp the kinetic and plastic character of this philosophical enterprise, which involves dynamic methodological procedures in view of the adaptation of the method to the object. We seek to achieve these objectives through two analyses: first, the analysis of the stages of the establishment of the articulated member paradigm (AMP), and then the analysis of the main analogy of the treatise, between the articulated limb and the animated automotricity. Through the two analyses we must gather the necessary elements to confront the two tenns of the main analogy, as well as to verify the general validity of the thesis and also the consideration according to which the analogical method of De Motu Animalium is a plastic instrument of the thought of immanence.

Cet ouvrage présente de nouveaux aspects de l’analogie entre temps et espace pour les ondes, à travers des concepts de contrôle temporel de la propagation des ondes, qui peuvent être interprétés comme la transposition au domaine temporel d’opérations standard du domaine spatial. Toute l’étendue de cette analogie est étudiée dans le cadre deux phénomènes ondulatoires bien connus (dans leurs versions spatiales), et dont nous montrons qu’ils sont étroitement liés : la réflexion des ondes et leur transformation par un cristal. En particulier, il est démontré expérimentalement que l’analogue temporel de la réflexion par un miroir génère une onde retournée temporellement, c’est-à-dire dont l’évolution temporelle est inversée. Une variante monofréquentielle de ce miroir temporel instantané, qui possède des liens étroits avec le concept de conjugaison de phase utilisé pour le retournement temporel d'ondes monochromatiques en optique, est également étudiée. Nous montrons que la modulation temporelle périodique du milieu mise en jeu dans ces expériences constitue l'équivalent temporel d'un cristal pour les ondes et étudions les propriétés générales des ondes dans ces milieux. Nous cherchons naturellement à sonder les limites de ces analogies spatiotemporelles, dont, de toute évidence, le principe de causalité est un élément majeur. Les phénomènes étudiés sont généraux et communs à toutes les ondes classiques, gouvernées en général par l’équation de d’Alembert ou par d’autres équations similaires. Les ondes à la surface d’un liquide sont utilisées comme système ondulatoire modèle dans nos expériences / This work presents new aspects of the analogy between time and space in wave phenomena, through new concepts of time control of wave propagation which can be interpreted as the transposition onto the time domain of standard spatial operations. The depth of this analogy is thoroughly studied in the framework of two well-known wave phenomena: reflection of waves on a mirror and their transformation by a crystal. More precisely, we experimentally demonstrate that the time analog of reflection by a mirror generates a time reverse wave that is whose time evolution is inverted. A monofrequency variant of this instantaneous time mirror, which has strong connections to the concept of wave phase conjugation used for time reversing monochromatic waves in optics, is also studied. We show that the periodic time modulation of the medium involved in the latter experiments constitutes the time equivalent of a crystal for waves and we study the general properties of waves in such media. We address of course the issue of the limits of theses space time analogies, of which, the principle of causality is evidently a major constituent. The phenomena studied here are general and apply to all classical waves (usually governed by d’Alembert’s equation or by similar ones). Waves at the surface of a liquid are used as a model wave system in our experiments / Die Universalitat der klassischen Wellenphanomenen lasst sich weitgehend durch die d’Alembertsche Struktur der Wellengleichungen beschreiben. In letzterer spielen die Zeit- und Raumvariabeln eine ahnliche Rolle. Wir betrachten in diesem Werk diese bekannte Analogie unter einem neuen Licht, indem wir neue Konzepte der Zeitkontrolle von der Wellenpropagation introduzieren, die als Transposition zum Bereich der Zeit von standarden Wellenphanomen des Raumes interpretiert werden konnen, wobei die raumliche Variation der Eigenschaften des Mediums, die sie bestimmen, durch eine zeitliche ersetzt wird. Wir bringen den experimentellen Beweis der Relevanz dieses Ansatzes, wobei wir die Wellen an der Oberflache einer Flussigkeit als Modelwellensystem verwenden und zeigen durch theoretische Erkenntnisse, dass er auf alle Wellensysteme generalisiert werden kann, die durch eine Wellengleichung beschrieben wird, deren 10 Struktur die der d’Alembertschen Gleichung ahnelt. Die ganze Reichweite dieser Analogie wird im Rahmen zweier langst bekannten Wellenphanomenen (in deren raumlichen Version), von denen wir zeigen, dass sie eng verbunden sind : die Spiegelung einer Welle und deren Umwandlung durch einen Kristal. Das Equivalent eines Spiegels fuhrt zur augenblicklichen Erscheinung aus dem gesammten Raum einer zeitumgekehrten Welle, das heist einer Wellenform, derer zeitliche Entwicklung im Vergleich zu der originellen Welle umgekehrt ist. Eine Einzelfrequenzvariante dieses augenblicklichen Zeitspiegels wird auch vorgestellt, die enge Verbindungen mit dem fur die Zeitumkehr monochromatischer Wellen angewendeten Konzept der optischen "Phase Conjugation" (Phasenkonjugierung) besitzt. Wir zeigen, dass die dazugehorige periodische Zeitmodulation des Mediums das zeitliche Equivalent eines Kristals fur die Welle bildet, und wir studieren die generellen Eigenschaften der Wellen in solchen Medien. Wir versuchen, die Grenzen dieser raumzeitlichen Analogien zu erkundigen, in derer Bestimmung selbstverstandlich das Kausalitatsprinzip eine masgebliche Rolle spielt, und die interessanten Unterschiede zwischen den vorgestellten Konzepten und deren raumlichen Pendants offenbaren / La universalidad de los fenomenos ondulatorios clasicos es ampliamente descrita por la estructura de la ecuacion de d’Alembert. En esta ecuacion, las variables espaciales y temporales desempenan un papel similar. En esa obra, revisitamos esta analogia bien conocida a traves de nuevos conceptos de control temporal de la propagacion de las ondas, quienes pueden ser interpretados como transposiciones de fenomenos espaciales estandartes al ambito temporal, en los cuales las variaciones espaciales de las propiedades del medio son reemplazadas por las correspondientes variaciones temporales. Hacemos la prueba, usando ondas a la superficie de un liquido, de la relevancia de este enfoque y mostramos teoreticamente su generalizacion a todo tipo de onda clasica, es decir gobernada por una ecuacion cuya estructura es similar a la de d’Alembert. Toda la extension de esta analogia queda estudiada en el cuadro de los dos fenomenos clasicos (en sus versiones espaciales) que son la reflexion de una onda sobre un espejo y su trasformacion en un cristal. Ademas, mostramos que los dos son intimamente relacionados. El equivalente temporal de un espejo produje instantaneamente desde el medio entero una onda retornada en el tiempo, es decir cuya evolucion temporal es invertida comparado a la onda inicial. Una variante monofrecuencial de este espejo queda estudiada tambien. Posee estrechos vinculos con el concepto de Phase Conjugation (conjugacion de fase), usado en Optica para hacer retornamiento temporal de ondas monocromaticas. Mostramos que la modulacion temporal implicada constituye el equivalente de un cristal para las ondas et estudiamos las caracteristicas generales de ondas en estos medios. Sondeamos los limites de esas analogias espaciotemporales de cuyos obviamente el principio de causalidad es un elemento mayor y que revelan diferencias interesantes entre los conceptos presentados y sus equivalentes espaciales / L’universalita dei fenomeni ondulatori classici e in larga misura descritta dalla struttura dell’equazione di d’Alembert. In quest’equazione, le variabili spaziali e temporali svolgono ruoli analoghi. Nell’opera seguente rivisitiamo questa ben nota analogia introducendo nuovi concetti sul controllo temporale della propagazione delle onde. Questi concetti possono essere interpretati come trasposizione di fenomeni ondulatori spaziali standard nell’ambito temporale, sostituendo le variazioni spaziali delle proprieta del mezzo con le variazioni temporali corrispondenti. Usando delle onde sulla superficie di un liquido come modello fisico, facciamo fede della rilevanza di quell’approccio e mostriamo teoricamente la generalizzazione a tutti i tipi di onde classiche, governate da equazioni simili a quella di d’Alembert. Questa analogia viene studiata nell’ambito di due fenomeni ondulatori ben noti (nella loro versione spaziale) : la riflessione delle onde generata da un specchio e la loro trasformazione generata da un cristallo. Mostriamo inoltre che i due concetti sono intimamente vincolati. L’equivalente temporale di un specchio porta alla generazione in tutto lo spazio di un’onda restituita nel tempo, vale a dire un’onda di cui l’evoluzione temporale e invertita in relazione all’onda originale. In questa tesi viene presentata anche una variante monofrequenziale di questo specchio temporale istantaneo che possiede legami stretti con il concetto di coniugazione di fase usato in ottica per invertire nel tempo onde monocromatiche. Mostriamo in questo lavoro che la modulazione temporale periodica del mezzo in questione costituisce, per le onde, l’equivalente temporale di un cristallo e ne studiamo le proprieta generali. In questa tesi, cerchiamo di sondare i limiti dell’analogia spaziotemporale, di cui il principio di causalita ne e l’essenziale e che rivelano differenze interessanti tra i concetti presentati e i loro equivalenti spaziali

Ce travail montre l'unité de l'œuvre de Pascal dans ce qui concerne la « comparabilité des incomparables » : la comparaison, langagière ou mathématique, qui se fait entre des choses qui ne pourraient pas en principe être rapprochées. Il s'agit de faire une approche historique et linguistique pour poser des questions philosophiques par rapport à la comparaison, notamment sur le rôle de principe que l'infini y joue selon Pascal. Nous identifions la comparaison des incomparables sous trois formes.La première partie de ce travail est consacrée à formuler une forme rhétorique d'analogie que nous nommons l'« analogie de disproportion » (nous inspirant de Secretan 1998). Si l'analogie est généralement dite faire une comparaison entre deux rapports, chacun desquels existe entre des choses homogènes, l'analogie de disproportion permet en revanche de montrer une ressemblance entre des rapports d'hétérogénéité, entre des disproportions ou entre des distances infinies: deux choses sont aussi différentes entre elles que deux autres. Pascal étant un auteur qui souligne surtout les disproportions, nous montrons qu'il compare ces disproportions, notamment pour délimiter à l'homme ce qu'il ne peut pas connaître parfaitement.La deuxième partie analyse la pratique mathématique de Pascal « en poids, nombre et mesure » : il s'agit de montrer que dans la méthode des indivisibles des Lettres de A. Dettonville, dans le Traité du triangle arithmétique et dans la comparaison du courbe et du droit, toujours l'infini (ou plutôt l'indéfini) intervient comme un facteur qui permet la comparabilité de ce qui semblait être incomparable. La troisième partie fait une discussion proprement philosophique sur l'infiniment petit et l'infiniment grand, prenant en compte la pratique mathématique de Pascal analysée dans la deuxième partie. Il est question de discuter sur la nature des « indivisibles », des « différences » et des « distances infinies ». Nous proposons que l'« infini » dans la pratique mathématique de Pascal relève plutôt de l'« indéfini », reliant cela à une distinction entre le sens absolu et le sens relatif des mots. Une exception dans la pratique mathématique de Pascal est la géométrie projective, où il faut accepter des éléments à distance infinie. La « rencontre » des deux infinis, finalement, permet de montrer la réciprocité de l'infini de grandeur et de l'infini de petitesse. Une discussion est faite à ce propos, reliant la proportion inverse entre les deux infinis à la grandeur et la petitesse de l'homme et au caractère paradoxal de certaines vérités selon Pascal, lesquelles sont résolues dans la personne du Christ. On conclut que Pascal propose non pas une connaissance directe de l'infini, mais plutôt une approche à la relation que l'homme, être fini, possède avec l'infini / This thesis shows the unity of Pascal's work in what concerns the "comparability of incomparables'': the comparison, either in mathematics our natural language, between things which could not in principle be brought together. The approach is both a historical and a linguistic one, and it aims to recovery some important questions regarding the philosophical nature of comparisons, more specifically, the role of the infinite in Pascal's thought. The comparison of incomparables may be identified in three different formsIn the first part, we formulate a rhetorical form of analogy that we call an "analogy of disproportion'' (inspired by Secretan 1998). If the analogy is generally said to make a comparison between two relations, each of which exists between homogeneous things, the analogy of disproportion, on the other hand, shows a resemblance between relations of heterogeneity, between disproportions or between infinite distances: two things may be as different from each other as any two other things. Even if disproportions are a central theme to Pascal, he did not shy away of comparing such disproportions -- in particular to delimit what man cannot know perfectly.The second part analyzes the mathematical practice of Pascal "in weight, number and measure'': it is necessary to show that in the method of indivisibles of the Lettres de A. Dettonville, in the Traité du Triangle Arithmétique and in the comparison of the curved and the straight lines, always the infinite (or rather the indefinite) intervenes as a factor that allows the comparability of what would seem to be incomparable. The third part makes a philosophical discussion on the infinitely small and the infinitely large, taking into account Pascal's mathematical practice, which was analyzed in the second part. We discuss the nature of "indivisibles'', "differences'' and "infinite distances''. We suggest that the "infinite'' in Pascal's mathematical practice is rather an "indefinite'', linking it to a distinction between the absolute and the relative meaning of words. An exception in Pascal's mathematical practice is his projective geometry, where it is necessary to accept elements at an infinite distance. The "encounter'' of the two infinites makes it possible to show the reciprocity of the infinity of greatness and the infinity of smallness. Finally, we analyze the inverse proportionality between the two infinites with regard to the greatness and the wretchedness of man and to the paradoxical nature of certain truths according to Pascal, which are concealed in the person of the Christ. The conclusion is that Pascal arrives not at a direct knowledge of the infinite, but to an approach to the relation that man, a finite being, has with the infinite

Analogy is ubiquitous in human cognition. One of the important questions related to understanding the situated nature of analogy-making is how people retrieve source analogues via their interactions with external environments. This dissertation studies interactive analogical retrieval in the context of biologically inspired design (BID). BID involves creative use of analogies to biological systems to develop solutions for complex design problems (e.g., designing a device for acquiring water in desert environments based on the analogous fog-harvesting abilities of the Namibian Beetle). Finding the right biological analogues is one of the critical first steps in BID. Designers routinely search online in order to find their biological sources of inspiration. But this task of online bio-inspiration seeking represents an instance of interactive analogical retrieval that is extremely time consuming and challenging to accomplish. This dissertation focuses on understanding and supporting the task of online bio-inspiration seeking. Through a series of field studies, this dissertation uncovered the salient characteristics and challenges of online bio-inspiration seeking. An information-processing model of interactive analogical retrieval was developed in order to explain those challenges and to identify the underlying causes. A set of measures were put forth to ameliorate those challenges by targeting the identified causes. These measures were then implemented in an online information-seeking technology designed to specifically support the task of online bio-inspiration seeking. Finally, the validity of the proposed measures was investigated through a series of experimental studies and a deployment study. The trends are encouraging and suggest that the proposed measures has the potential to change the dynamics of online bio-inspiration seeking in favor of ameliorating the identified challenges of online bio-inspiration seeking.

The thesis utilizes the analogy in dynamic equations between a mechanical and an electrical system to convert the steam-turbine, micro-turbine, wind-turbine and hydro-turbine generator mechanical model to equivalent electrical circuit models respectively. And based on the round rotor type and permanent magnetic rotor type synchronous generators¡¦ dynamic equations, as well as their electromagnetic torque equations, the equivalent electrical interface circuits were derived respectively. By using the interface circuit, the circuit model of synchronous generator and the equivalent electrical circuit model of turbine-generator mechanism can thus be combined into the electromechanical integrated circuit model (Thevenin¡¦s analogy circuit model and Norton's analogy circuit model). The electromechanical integrated circuit model is helpful for analyzing the energy conversion, power transmission and interactions between the mechanical and electrical systems for a turbine generator unit. In order to learn about these electromechanical interactions by using the proposed electromechanical integrated circuit model, the thesis has made a study on the torsional vibrations for a small gas turbine generator unit and for a large steam turbine generator unit respectively. By way of the frequency scanning and eigenvalue calculation, it is found that the torsional mode frequencies can be changed due to the electromechanical integration. Moreover, the small unit was more affected by the electromechanical integration than the large unit. Finally, we studied the effect of operations of an Electric Arc Furnaces (EAF) on torsional vibrations of a low capacity turbine generator. The electric system studied belongs to a practical steel plant in an industrial park. Based on the electromechanical integrated equivalent circuit model, a flywheel coupling shaft was designed. It is found by simulations that the coupling shaft can be quite effective in alleviating vibrations caused by the system unbalance arising from the EAF operations.

In this study, the effects of design parameters on the fan noise level are investigated both theoretically and experimentally. For the theoretical study, a computational aero- acoustic method is used to predict the flow induced noise of a fan. This method involves the coupling of a flow solver and a wave equation solver. Unsteady flow analysis is performed with URANS using FLUENT. Then the time dependent data are processed with LMS Sysnoise to compute the acoustic radiation. Experimental studies are performed to verify the theoretical results and additionally to investigate the effects of different design alternatives on noise level of the fan. The sound pressure and intensity level measurements are performed in the full anechoic room of Ar&ccedil / elik A.S. Research and Development Laboratories. The validation experiments indicate that there is a good agreement between numerical and experimental results. The experimental study with different fan designs gives information about the noise reduction possibilities.

This study presents the theoretical analysis of an active flutter suppression methodology applied to a smart fin. The smart fin consists of a cantilever aluminum plate-like structure with surface bonded piezoelectric (PZT, Lead- Zirconate-Titanate) patches. A thermal analogy method for the purpose of modeling of piezoelectric actuators in MSC&reg / /NASTRAN based on the analogy between thermal strains and piezoelectric strains was presented. The results obtained by the thermal analogy were compared with the reference results and very good agreement was observed. The unsteady aerodynamic loads acting on the structure were calculated by using a linear two-dimensional Doublet-Lattice Method available in MSC&reg / /NASTRAN. These aerodynamic loads were approximated as rational functions of the Laplace variable by using one of the aerodynamic approximation schemes, Roger&amp / #8217 / s approximation, with least-squares method. These approximated aerodynamic loads together with the structural matrices obtained by the finite element method were used to develop the aeroelastic equations of motion of the smart fin in state-space form. The Hinf robust controllers were then designed for the state-space aeroelastic model of the smart fin by considering both SISO (Single-Input Single-Output) and MIMO (Multi-Input Multi-Output) system models. The verification studies of the controllers showed satisfactory flutter suppression performance around the flutter point and a significant improvement in the flutter speed of the smart fin was also observed.

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